1. Field of the Invention
The present invention relates to an insertion system which detects an insertion amount and a rotation amount of an insertion member to be inserted into a lumen through an insertion portion.
2. Description of the Related Art
In general, an insertion system of an endoscope has an insertion portion to be inserted into an insertion target, an insertion hole to insert at least an insertion member such as a treatment instrument, and an operation portion to curve the insertion portion. The insertion portion is provided with a channel which passes through the insertion portion from the insertion hole to the distal end and through which the insertion member is inserted. The insertion member is, for example, a member in which a treatment portion such as a grasp member or a cutting member is provided at the distal end of a cable member.
As an insertion member, for example, Jpn. Pat. Appln. KOKAI Publication No. 2010-22619 has disclosed a configuration in which at the proximal end (insertion-hole-side end) of a flexible cable, a rotational operation portion for adjusting the direction of the distal end of this cable is provided. This rotational operation portion is frictionally engaged with the outer circumferential portion of the cable of the insertion member. If the rotational operation portion is rotationally operated, rotational force in the direction around the axis of the rotation is transmitted to the cable in the frictionally engaged state, so that the position of the distal end of the insertion member in the direction around the axis can be adjusted by the proximal end of the cable.
In the above-mentioned Jpn. Pat. Appln. KOKAI Publication No. 2010-22619, when the insertion member is inserted in the channel of the insertion portion, it is difficult for an operator to accurately recognize the insertion position of the distal end of the insertion member and its rotational direction around the axis while observing an endoscopic observation image. It is also difficult for the operator to accurately recognize the insertion position of the distal end of the insertion member and its rotational direction around the axis through manual sensation by the operator when the operator has inserted the insertion member in the channel of the insertion portion.
An object of the present invention is to provide an insertion system that makes it possible to accurately recognize the insertion position and direction of an insertion member by detecting operation support information such as an insertion amount and a rotation amount of the insertion member, and the position and shape of the distal end thereof.